Finishing her bag of Karu cheese-flavoured snacks, Shoko Taketani blushes and admits that she still feels oddly peckish. It is not her imagination: Japanese crisp packets contain 10 per cent fewer crisps than they did a month ago.

In Munich, beer at this year’s Oktoberfest will be the most expensive in the festival’s history and Matthaias Hickl is breaking the habit of a lifetime: he is staying away in protest.

In Kuala Lumpur, Rhosdi is mulling a decision he thought would always be beyond him: whether to trade in his motor scooter for his first car. He is one of the 1.2 million Malaysian civil servants who have just received a windfall pay increase — their first in 15 years.

Though geographically diverse and apparently unrelated, these developments are in fact connected, symptoms of a new global trend. Stomachs and petrol tanks are for the first time in competition and farmers everywhere are asking themselves a novel question: am I planting food or energy?

There is no single source for the revolution sweeping across every continent. But one starting point is Jim Curl’s 350-acre farm in Brahman, Oklahoma. This year he planted a third of it with genetically modified corn instead of the area’s traditional crop of wheat.

This amounts to 100 acres or so, a mere flap of a butterfly’s wings in the great scheme of things. But by the time the impact of Mr Curl’s decision has made its way to the other side of the world, the results are seismic.

The economics of food — what is affordable, what it costs, and what that money buys — are creating unprecedented waves through all continents. From nut plantations in Indonesia to barley fields along the Rhine, farmers are all adjusting to this new world.

Part of the result is tortilla riots in Mexico, the astonishing leap in Brazilian chicken leg prices and mayonnaise price spikes in Western Europe.

These, say industry insiders, are the first skirmishes of a conflict that could soon dominate geopolitics: the war for resources between the world’s 800 million cars and its six billion stomachs. In the developed world, the war will come down to price and choice; in the developing world it could come down to survival.

The war centres largely on global demand for biofuels — “green” replacements for petrol, such as ethanol, that can be produced from sugar, corn and other agricultural products rather than fossil fuels.

Farmers are making a perfectly rational economic choice. With the price of crude oil high, they are planting crops to meet demand for cheaper biofuels. But converting more crops into energy means there is less to go into foodstuffs. And so the price of those foodstuffs rise.

The price increases for German beer, for instance, arise from replacing barley fields with ethanol feedstocks. And the consequences are widespread.

“I’m not going to the Oktoberfest this year,” Mr Hickl said. A Bavarian based in Milan, the 40-year-old artist is accustomed to joining countrymen on the annual pilgrammage to perhaps the world’s biggest drunken party. But no more. “The price of a measure is heading up towards ¤eight euros<NO>and at that rate only tourists and the super-rich can afford to get drunk,” Mr Hickl said. “I’m furious — and I’m not going.”

The US is a driving force in such change. In January President Bush called for a massive increase in the use of ethanol over the next decade — a move regarded by traders as setting the battle lines of the future conflict. America now devotes more acreage to growing corn than at any time since 1944. Farmers planted 90.5 million acres this year, 15 per cent more than 12 months ago. But little of it will go anywhere near a dinner plate.

If White House targets to double ethanol production by next year are achieved, and in due course 40 per cent of that corn ends up in petrol tanks, the world may have a difficult, expensive time feeding itself.

This emphasis on ethanol as the biofuel of choice, said Michael Lewis, Deutsche Bank’s head of commodities research, has created unprecedented competition between food and energy. “Agricultural commodities are the subject of a growing battle between the demands of automobiles in the US and the demands of feeding people in the developing world,” he said.

In Oklahoma, the choice for farmers like Mr Curl is a micro one. Some 80 ethanol refineries are being built in the US, to add to the 114 already up and running. One is planned near Mr Curl’s farm. “It should raise the price quite a bit,” he said — possibly to as much as $4 a bushel from the current $3.50-$3.60. And so instead of producing food, a third of Mr Curl’s land is growing future energy.

Once copied across a continent, such decisions mean farming states could become as big a player in global energy markets as a member of Opec (the Organisation of Petroleum Exporting Countries).

Mr Curl’s decision has momentous consequences. Planting more corn for ethanol has meant a 15 per cent cut in the amount of land devoted to soya. So soya oil prices are rising. That in turn has opened the door to cheaper palm oil — 90 per cent of which comes from Malaysia and Indonesia.

That surge in sales of palm oil is, in Malaysia in particular, creating dramatic social change overnight. Government coffers are so full that last month all civil servants — everyone from deputy public prosecutors to ministry cooks — were given pay rises of between 7.5 per cent and 42 per cent. The one-off windfall was their first salary increase since 1992 and cost the Government £1.1 billion. To make life even sweeter, the cost-of-living allowance for the same workers — who represent about a tenth of the country’s workforce — was doubled.

Suddenly, people in one of Malaysia’s most underpaid and conservative sectors are talking about dipping their toes in the stock market, buying homes and upgrading their lifestyles.Rhosdi, for instance, a state-school teacher in his 30s, is able to think about the social advance involved in swapping two wheels for four.

Envious of the civil servants’ good fortune, private sector employees have begun lobbying for similar pay rises. Tellers at branches of Maybank in Kuala Lumpur have begun wearing prominent signs around their necks demanding that management “match the civil servants’ increase”.

In this complex train of economic cause and effect, there is another butterfly flapping its wings in Beijing in the shape of Liu Ping. She used to buy her monthly quota of half a pound of oil for the three members of her family with a ration coupon.

“The oil just about filled a beer bottle and we had to make do for a month.” That was in the 1960s and 1970s, when the family used to steam most of their food. “We just didn’t cook dishes that needed lots of oil, like eggplant or beans.” Some people used lard even in the 1980s when oil was at last available in the shops, but at a cost of 1 yuan per kilo – a lot for the average family living on 40 yuan a month.

Now Mrs Liu, 60, uses about 6 catties (pounds) of oil a month to cook for her husband and daughter, underlining how economic growth in China — and India — has created vast new markets for edible oils, particularly soya and palm oil.

Diets in China and India have changed out of recognition as prosperity has grown, creating greater demands for meat and, as a consequence, the crops that feed livestock.

Dairy is also affected. Chinese, for instance, will by 2020 be consuming about 40kg of milk per capita compared with today’s average 24kg. Milk, yoghurt, and cheese form an increasingly large proportion of urbanites’ diet. Ice cream has emerged as a favourite snack.

But it is corn — global inventories are at a record low and the price of the crop is 50 per cent higher than it was last year — and edible oils where the greatest impact is being be felt.

As the billion-strong populations of both countries gradually rise from poverty, vegetable oils – an extremely expensive proportion of the average developing world diet – have formed a greater part of everyday meals.

In Beijing, a ten-litre bottle of oil costs about 80 yuan — inexpensive for today’s new-rich city dwellers and affordable even to China’s farmers.

Within a year, say economists, China could reach the hugely significant point of becoming a net importer of corn. Oils give food a sophistication that more and more Chinese and Indians are getting a taste for.

Shoko Taketani, with her empty crisp packet in Tokyo, knows this to her cost.

— Additional reporting by James Bone in New York, Roger Boyes in Berlin and Jane Macartney in Beijing

Corn on the hop

27%: of this year’s record 12.46 billion bushel corn harvest in America will be used by the biofuel industry

15%: is the most petrol use that could be offset even if all the corn used in America were used to produce biofuel

15%: of all arable land in Europe will be needed if the EU is to meet its target of ensuring that 10% of transport is driven by biofuels 2020

Explore Asia News

• China News

Times Recommends

• Putin set to bait US with nuclear aid for Tehran
• North Korea ‘uses doubles to hide death of Kim’
• Academics label Charlie Wilson too 'gung-ho'